diff --git a/lib/io_monitor/controller.rb b/lib/io_monitor/controller.rb
index 1a043c7..b9d6e1d 100644
--- a/lib/io_monitor/controller.rb
+++ b/lib/io_monitor/controller.rb
@@ -37,7 +37,7 @@ def append_info_to_payload(payload)
         data[source] = aggregator.get(source)
       end
 
-      data[:response] = payload[:response].body.bytesize
+      data[:response] = payload[:response]&.body&.bytesize || 0
     end
 
     private
diff --git a/lib/io_monitor/patches/net_http_adapter_patch.rb b/lib/io_monitor/patches/net_http_adapter_patch.rb
index 4f3c953..a6ef49a 100644
--- a/lib/io_monitor/patches/net_http_adapter_patch.rb
+++ b/lib/io_monitor/patches/net_http_adapter_patch.rb
@@ -3,8 +3,8 @@
 module IoMonitor
   module NetHttpAdapterPatch
     def request(*args, &block)
-      super do |response|
-        if response.body && IoMonitor.aggregator.active?
+      super.tap do |response|
+        if response&.body && IoMonitor.aggregator.active?
           IoMonitor.aggregator.increment(NetHttpAdapter.kind, response.body.bytesize)
         end
       end
diff --git a/spec/dummy/app/controllers/fake_controller.rb b/spec/dummy/app/controllers/fake_controller.rb
new file mode 100644
index 0000000..9159c53
--- /dev/null
+++ b/spec/dummy/app/controllers/fake_controller.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class FakeController < ApplicationController
+  include IoMonitor::Controller
+
+  def fake
+    raise ActionController::RoutingError.new("Fake")
+  end
+end
diff --git a/spec/dummy/config/routes.rb b/spec/dummy/config/routes.rb
index edf04d2..ca6b71d 100644
--- a/spec/dummy/config/routes.rb
+++ b/spec/dummy/config/routes.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
 
 Rails.application.routes.draw do
+  get "/fake", to: "fake#fake"
 end
diff --git a/spec/io_monitor/controller_spec.rb b/spec/io_monitor/controller_spec.rb
index 3237710..9431091 100644
--- a/spec/io_monitor/controller_spec.rb
+++ b/spec/io_monitor/controller_spec.rb
@@ -133,3 +133,11 @@ def show
     end
   end
 end
+
+RSpec.describe "when response is nil", type: :request do
+  it "does not fail" do
+    get "/fake"
+
+    expect(response).to be_not_found
+  end
+end